Bill, what you are saying is correct... increasing fuel pressure does in fact make a fuel injector act like a larger injector than what it is 'rated' for. In fact if you look up the specs for any injector, they don't just list the flow rating, but also provide the pressure at which that rating applies.
This is an old school trick, which was used with great success for a long time. There is some risk... specifically very short pulse widths in low rpm situations can cause erratic fueling. This is why today, we call it a band-aid...
If it is working for you, great!
You could install a WBO2, and confirm that the ecu is able to hit the target AFR's, or watch fuel trims if you have that capability?